Various compounds are known as alkoxysilanes that have a phenol group or a catechol group. Organosilicon resins prepared with these alkoxysilanes have excellent alkali-solubility and are used as additives to resins, electronic materials and various reactable base materials (cvf. Patent Document 1, Patent Document 2). However, each of these resins has a phenol group and therefore absorbs ultraviolet radiation. Because of the absorption, the resins are problematic with respect to important qualities including transparency, weatherability, microfabricating ability and the like.
Recently, a variety of alkali-soluble resins have developed and an organosilicon resin in which a carboxyl group is introduced is reported (cf. Patent Document 3).
However, it is difficult to obtain an excellent alkali-solubility by using these organosilicon resins having a carboxyl group comparable to the case of a phenol group. An improvement of the alkali-solubility has been desired. A hexafluorocarbinol group a has almost the same pKa (9.82) as phenol and possesses an excellent alkali-solubility. Therefore, an organosilicon compound containing a hexafluorocarbinol group is receiving increased attention.
Trichlorosilane wherein a hexafluorocarbinol group has been protected by an organic group is so far known (cf. Patent Document 4). The reaction for obtaining this compound is a hydrosilylation reaction in which a compound having a hexafluorocarbinol group and a carbon-carbon unsaturated group, and trichlorosilane are starting materials. The reason why a starting material wherein a hexafluorocarbinol group has been protected by an organic group is used in this reaction is to prevent from reacting a chlorosilyl group of the chlorosilane as another starting material and a hexafluorocarbinol group.
In the above-mentioned production process using trichlorosilane as a starting material, since a compound having a hexafluorocarbinol group can be obtained when a de-protecting step of a hexafluorocarbinol group is performed after hydrosilylating, there is a problem leading to a complicated production step.
[Patent Document 1] JP-A-2002-179795
[Patent Document 2] JP-A-2002-338583
[Patent Document 3] JP-A-2001-005185
[Patent Document 4] JP-A-2002-55456